Giraffes have as many vertebrae as a human being. Yet the neck of a giraffe is in general 2 meters long, and the neck of a human being is in general only 15 centimeters long. Recently, some research is done to the genes of giraffes to understand the underlying reason why giraffes have long necks. In order to detect exceptions in the DNA, researchers have compared the DNA of a giraffe with the DNA of an okapi. The okapi is closely related to the giraffe and therefore this DNA can be well used for comparison. The main difference between an okapi and a giraffe is the long neck of a giraffe.
What makes a giraffe unique?
Another important item of giraffes is the cardiovascular capacity. Due to the long neck, it takes more effort to pump blood into the head. Therefore the heart of a giraffe is extra strong and partly bigger.
The study found 70 genes that are unique to giraffes. About half of these are known to regulate the growth and development, of particularly the skeleton, and the circulatory system. These two things are unique to a giraffe. A number of these genes work together in order to lengthen the cervical spine. Humans have flat discs as vertebrae. Giraffes have long, stretched vertebrae, which extends the length of the neck.
A mutation in one of the 70 genes whose function is not entirely clear in giraffes, creates defects in bone and cardiovascular developments in humans and mice. It may, therefore, be the case that these genes may be responsible for one of the unique characteristics of a giraffe.
Up to now, researchers did not study the complete genome of a giraffe. At this time, the focus has been to study the pieces of DNA that code for proteins. The next step is to also study the other parts of the DNA of giraffes, in order to form a complete picture. It is not yet known what the purpose of the genes is that do not affect proteins. Perhaps here lies another interesting discovery regarding the unique features that make a giraffe a giraffe.
Read the article about the research.